<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>CSS Grid Layout</title>
  <link rel="stylesheet" href="styles.css">
</head>
<style>
  /* styles.css */
body {
  margin: 0;
  font-family: Arial, sans-serif;
}

.grid-container {
  display: grid;
  grid-template-areas:
    "header header"
    "sidebar main-content"
    "footer footer";
  grid-template-rows: 60px 1fr 30px;
  grid-template-columns: 200px 1fr;
  height: 100vh;
}

.header {
  grid-area: header;
  background-color: #f4f4f4;
  padding: 10px;
  border-bottom: 1px solid #ddd;
}

.sidebar {
  grid-area: sidebar;
  background-color: #eee;
  padding: 10px;
  border-right: 1px solid #ddd;
}

.main-content {
  grid-area: main-content;
  padding: 10px;
}

.footer {
  grid-area: footer;
  background-color: #f4f4f4;
  padding: 10px;
  border-top: 1px solid #ddd;
}
</style>
<body>
  <div class="grid-container">
    <header class="header">Header</header>
    <aside class="sidebar">Sidebar</aside>
    <main class="main-content">Main Content</main>
    <footer class="footer">Footer</footer>
  </div>
</body>
</html>